1. Field of the Invention
This invention relates to a method for quantitating organic oxidants, and is especially useful in detecting low amounts of peracid as low as about 0.3 ppm A.O.(parts per million active oxygen) in systems containing high amounts of hydrogen peroxide.
2. Brief Description of Related Art
Standard titration techniques have been developed for the quantitative determination of organic oxidants, such as organic peracids. S. N. Lewis, xe2x80x9cPeracid and Peroxide Oxidations,xe2x80x9d in: Oxidation (Marcel Dekker, 1969).
Various other quantitative assays have been developed, e.g., electrochemical determination, but these prior art systems suffer from the inability to detect small quantities of organic oxidants in the presence of hydrogen peroxide.
Cox et al, U.S. Pat. No. 4,421,668, discloses a liquid bleach composition containing a hydrogen peroxide precursor comprising an alcohol oxidase and, as the substrate for the oxidase, a specific alcohol. The patent mentions that within the cell-free extract of alcohol oxidase, there is some catalase naturally present as a contaminant (column 5, lines 26-32.) Cox also notes that it is preferred to limit the amount of catalase present in the claimed liquid composition.
Clements et al, U.S. Pat. No. 4,338,210, discloses a low temperature bleach composition comprising a peracid precursor system, and a source of bromide ions. The patent notes that if there is an excess of sodium perborate present in the peracid precursor system, such excess amounts can be scavenged by including a discrete quantity of catalase (column 6, lines 14-59).
However, none of the prior art discloses, teaches or suggests that catalase is an efficient scavenger or quenching agent for hydrogen peroxide, without affecting the organic oxidant being assayed. Further, nothing in the prior art discloses, teaches or suggests that catalase may act as a selective oxidant for hydrogen peroxide. Moreover, none of the prior art discloses, teaches or suggests that a quantitative method using catalase as a scavenging or quenching agent for hydrogen peroxide can detect very low quantities of organic oxidant against a large background of hydrogen peroxide.
The invention relates to a method for quantitating organic oxidants in which an amount of catalase is introduced into a solution containing the organic oxidant and hydrogen peroxide, the amount being sufficient to decompose the hydrogen peroxide. Thereafter, the organic oxidant is quantitated by known methods.
It is therefore an object of this invention to provide a method for quantitatively determining organic oxidants present in a solution.
It is a further object of this invention to provide a method for detecting very low quantities of organic oxidants in a solution.
It is also an object of this invention to provide a quantitative assay which can detect low amounts of organic peracids in a solution in the presence of a high background of hydrogen peroxide.
It is yet another object of this invention to provide a method of quantitating organic oxidants in which background hydrogen peroxide can be quenched or scavenged without significantly affecting the organic oxidants contained therein.